STENT

Abstract

The present invention relates to a stent for transluminal implantation into hollow organs, in particular into blood vessels, ureters, esophagi, the colon, the duodenum, the airways or the biliary tract, comprising an at least substantially tubular body that extends along a longitudinal direction and that can be converted from a compressed state having a first cross-sectional diameter into an expanded state having an enlarged second cross-sectional diameter, wherein the stent comprises a stent body composed of a biostable material, characterized in that the stent body comprises a plurality of stent sections, preferably annular stent sections, that are in particular separate from one another, and the stent has a support structure that connects the stent sections to one another, wherein the support structure is formed from a bioresorbable material or comprises a bioresorbable material.

Claims

1. A stent for transluminal implantation into hollow organs, the stent comprising an at least substantially tubular body that extends along a longitudinal direction and that can be converted from a compressed state having a first cross-sectional diameter into an expanded state having an enlarged second cross-sectional diameter, wherein the stent comprises a stent body composed of a biostable material, wherein the stent body comprises a plurality of stent sections and the stent has a support structure that connects the stent sections to one another, wherein the support structure is formed from a bioresorbable material or comprises a bioresorbable material.

2. The stent in accordance with claim 1, wherein the support structure is configured to hold the stent sections in a defined relative position to one another, and/or wherein the support structure is arranged at least substantially at the outer side of the stent body.

3. The stent in accordance with claim 1, wherein the support structure comprises a plurality of rails that extend at least substantially in parallel with the longitudinal direction.

4. The stent in accordance with at least claim 3, wherein at least one of the rails comprises at least one spring element that has an increased flexibility in comparison with the flexibility of the rail in the region outside the spring element.

5. The stent in accordance with claim 1, wherein the support structure is fastened to the stent body by means of a form fit and/or a force fit.

6. The stent in accordance with claim 1, wherein, for fastening the support structure to the stent body, the stent body has a fastening projection around which the support structure runs at least in part.

7. The stent in accordance with claim 1, wherein, for fastening the support structure, the stent body is hooked to the support structure, by means of two fastening rings, and wherein at least one of the fastening rings is open.

8. The stent in accordance with claim 1, wherein the support structure comprises a plurality of rails that extend at least substantially in parallel with the longitudinal direction, wherein at least one of the rails comprises at least one spring element that has an increased flexibility in comparison with the flexibility of the rail in the region outside the spring element and wherein the support structure comprises a plurality of cylinder segments in the interior of the stent body.

9. The stent in accordance with claim 1, wherein the support structure comprises a plurality of recesses and/or depressions in which stent sections of the stent body come to lie.

10. The stent in accordance with claim 1, wherein an inwardly disposed support structure has a different degradation behavior than an outwardly disposed support structure.

11. The stent in accordance with claim 1, wherein at least two stent sections of the stent body are connected to one another by connection elements formed from the material of the stent body, wherein parts of the support structure are attached to the connection elements to reinforce the connection elements.

12. The stent in accordance with claim 1, wherein the support structure presses against the stent body in at least one fastening recess of the stent body to fasten the support structure to the stent body by means of a force fit.

13. A stent system comprising a stent for transluminal implantation into hollow organs, the stent comprising an at least substantially tubular body that extends along a longitudinal direction and that can be converted from a compressed state having a first cross-sectional diameter into an expanded state having an enlarged second cross-sectional diameter, wherein the stent comprises a stent body composed of a biostable material, wherein the stent body comprises a plurality of stent sections, and the stent has a support structure that connects the stent sections to one another, wherein the support structure is formed from a bioresorbable material or comprises a bioresorbable material and a catheter in which the stent is received or can be received in a compressed state.

14. The stent system in accordance with claim 13, wherein the catheter is configured to set or to change a spacing of the stent sections from one another during the release and/or to rotate the stent sections with respect to one another during the release.

15. A method of manufacturing a stent comprising an at least substantially tubular body that extends along a longitudinal direction and that is convertible from a compressed state having a first cross-sectional diameter into an expanded state having an enlarged second cross-sectional diameter, wherein the stent comprises a stent body composed of a biostable material, wherein the stent body comprises a plurality of stent sections, and the stent has a support structure that connects the annular stent sections to one another, wherein the support structure is formed from a bioresorbable material or comprises a bioresorbable material, wherein, in the method, a force is applied to the support structure already contacting the stent body in order to bring about a deformation of the support structure.

16. The stent in accordance with claim 1, wherein the stent sections are annular stent sections.

17. The stent in accordance with claim 1, wherein the stent sections are separate from one another.

18. The stent in accordance with claim 3, wherein the rails are uniformly distributed in the peripheral direction of the tubular body and/or have an equal length in the longitudinal direction and/or have different positions in the longitudinal direction.

19. The stent in accordance with at least claim 4, wherein the spring element is arranged between two annular stent sections.

20. The stent in accordance with at least claim 19, wherein the spring element is arranged centrally between two annular stent sections.

21. The stent in accordance with claim 6, wherein the fastening projection is in a recess of the stent body and/or projects from the recess.

22. The stent in accordance with claim 7, wherein the two fastening rings engage into one another.

23. The stent in accordance with at least claim 7, wherein a hooking of the stent body and the support structure is achieved by means of a barb guided through an opening.

24. The stent in accordance with claim 8, wherein the cylinder segments form a cylinder or a hollow cylinder in a compressed state of the stent.

25. The stent in accordance with claim 10, wherein the inwardly disposed support structure is more quickly biodegradable than the outwardly disposed support structure.

26. The stent system in accordance with claim 13, wherein the catheter has depressions at an inner wall, in which depressions the support structure of the stent comes to lie.

Description

[0074] The invention will be described purely by way of example with reference to the drawings in the following. There are shown:

[0075] FIG. 1 schematically, a stent with a stent body and a support structure in accordance with a first embodiment;

[0076] FIG. 2 schematically, the cells of a stent and rails of the support structure in accordance with a second embodiment;

[0077] FIG. 3 schematically, the cells of a stent and rails of the support structure in accordance with a third embodiment;

[0078] FIG. 4 schematically, the connection of the support structure to the stent body in accordance with a fourth embodiment;

[0079] FIG. 5 schematically, the fastening of the support structure to cells of the stent body in accordance with a fifth embodiment;

[0080] FIG. 6 schematically, the connection of the support structure to the stent body in accordance with a sixth embodiment;

[0081] FIG. 7 a stent body and a support structure that is configured as a hollow cylinder divided into cylinder segments in the interior of the stent body (seventh embodiment);

[0082] FIG. 8 schematically, connection elements between stent sections that are reinforced by a bioresorbable material (eighth embodiment); and

[0083] FIG. 9 a support structure in accordance with a ninth embodiment, wherein the support structure comprises depressions in which stent sections come to lie.

[0084] FIG. 1 shows a stent 10 of a first embodiment in the expanded state. The stent 10 has a tubular shape and extends along a longitudinal direction L. The stent comprises a tubular stent body 12, wherein the stent body 12 is connected to a support structure 14. In FIG. 1, the support structure 14 is shown in the form of a plurality of rails 16.

[0085] The stent body 12 is formed from a biostable material, for example, nitinol. The support structure 14, in contrasts, consists of a bioresorbable material, for example, a zinc alloy.

[0086] For the further embodiments, essentially only the differences from the embodiment of FIG. 1 are explained.

[0087] FIG. 2 shows a second embodiment of the stent 10. FIG. 2 in this respect shows a section of an unwinding of the stent 10. The stent body 12 is formed from cells 18. The cells 18 each have a diamond shape and are formed from strut-like bordering elements 20.

[0088] The stent 10 can each have additional cells 18 that are not shown in the Figures.

[0089] The cells 18 shown at the top in FIG. 2 are each connected to the cells 18 shown at the bottom in FIG. 2 to create the tubular shape of the stent body 12 in this manner. The cells 18 of the stent 10 each form annular stent sections 22 that are separate from one another. Each stent section 22 has a row of cells 18 that are connected to one another in the peripheral direction. The cells 18 of a stent section 22 are each connected to the cells 18 adjacent in the peripheral direction via two connection sections 24.

[0090] The rails 16 are each coupled to the stent body 12 in the region of the connection sections 24. The rails 16 are elongated and straight and extend over the total length of the stent body 12. The individual stent sections 22 themselves are only connected to one another via the rails 16 of the support structure 14.

[0091] FIG. 3 shows a third embodiment of the stent 10. The third embodiment differs from the embodiment in accordance with FIG. 2 in that the rails 16 each have a spring element 26 between two stent sections 22. The spring element 26 comprises a tapering 28 that is part of a meandering structure 30. The spring elements 26 allow a certain movability of the stent sections 22 with respect to one another.

[0092] FIG. 4 shows a fourth embodiment, wherein one possibility of connecting the support structure 14 to the stent body 12 is shown. FIG. 4 shows recesses 32 formed in connection sections 24, wherein a fastening projection 34 projects into the recesses 32. Loops 36 or arcs 38 of the support structure 14 can then be placed around the fastening projections 34 to fasten the support structure 14 to the stent body 12.

[0093] The fifth embodiment shown in FIG. 5 likewise comprises fastening projections 34 around which loops 36 of the support structure 14 are placed. In contrast to the embodiment of FIG. 4, the fifth embodiment comprises elliptical cells 18. Furthermore, the fifth embodiment shows rails 16 that are each only fastened to each second stent section 22 (viewed in the longitudinal direction L). Furthermore, the rails 16 are formed shorter than the length of the stent body 12.

[0094] FIG. 6 shows a sixth embodiment of the stent 10. In the sixth embodiment, the support structure 14 is connected to the stent body 12 by means of fastening rings 40. Both the stent body 12 and the support structure 14 have fastening rings 40 in this respect. The fastening rings 14 of the stent body 12 can in this respect be open and have a slot (not shown) through which the fastening ring 40 of the support structure 14 can engage in the fastening ring 40 of the stent body 12. Accordingly, the fastening rings 40 of the support structure 14 can be closed fastening rings 40.

[0095] In the embodiment in accordance with FIG. 6, the individual stent sections 22 can also be connected to one another by material of the stent body 12, more precisely by connection elements 42. The connection elements 42 each extend from an end of a diamond-shaped cell 18 of a stent section 22 up to an end of a cell 18 of a directly adjacent stent section 22.

[0096] FIG. 7 shows a seventh embodiment of a stent 10 in the expanded state. FIG. 7 in this respect shows a view in the direction of the longitudinal axis L. Within the stent body 12, the support structure 14 comprises a plurality of cylinder segments 44 that form a hollow cylinder in the compressed state. The cylinder segments 44 form inwardly disposed rails 16 within the stent body 12.

[0097] FIG. 8 shows an eighth embodiment of the stent 10 in which the stent sections 22 are connected by connection elements 42. In the upper region of FIG. 8, a part of an unwinding of the stent 10 is shown for this purpose (top view). In the lower part of FIG. 8, a side view of a connection element 42 is shown. The connection element 42 is formed from a biostable material of the stent body 12 and is reinforced by a bioresorbable material of the support structure 14. The material of the support structure 14 serving for the reinforcement is received in a receiver 46 of the connection element 42, wherein the receiver 46 can e.g. be formed by a recess in the connection element 42.

[0098] FIG. 9 shows a ninth embodiment of the stent 10, wherein a schematic side view of the stent 10 is shown. The stent 10 again comprises a plurality of stent sections 22 that are connected to a support structure 14, wherein a rail 16 of the support structure 14 is shown in FIG. 9. The rail 16 comprises a plurality of positioning recesses 48 in which the stent sections 22 come to lie and are held in predefined positions relative to one another in this manner. A thickened portion 50 of the rail 16 is provided between the positioning recesses 48.

[0099] As stated above, the different embodiments can be combined with one another. For example, the positioning recesses 48 can also be integrated in the rails 16 of the preceding embodiments. It is likewise possible to combine different connection methods between the stent body 12 and the support structure 14 with one another.

[0100] It is a common feature of all the embodiments that the support structure 14 causes an increased stability of the stent 10 during the insertion into a hollow organ. The support structure 14 is only temporarily present after the insertion and is resorbed, wherein the advantage of an increased flexibility of the stent 10 is given after the resorption.

TABLE-US-00001 Reference numeral list 10 stent 12 stent body 14 support structure 16 rail 18 cell 20 bordering element 22 stent section 24 connection section 26 spring element 28 tapering 30 meandering structure 32 recess 34 fastening projection 36 loop 38 arc 40 fastening ring 42 connection element 44 cylinder segment 46 receiver 48 positioning recess 50 thickened portion